lindquist



Dec. 22, 1925 1,566,491 D. L. LlNDQUlST v SAFETY MECHANISM FOR ELEVATORS 2 Sheets-Sheet 1 Filed Jan. 10 192 J o m w a I la FIG. Z

- gwucmtoz 11M L L' $3 Sworn-e4 Dec. 22, 1925.

D. L. LINDQUIST SAFETY MECHANISM FOR ELEVATORS 2 Sheeis-Sheat 2 Filed Jan. 10, 1924 Lb Prat an 've/nto'z 13 LLW Paten UNITED STA DAVI COMPANY, OF JERSEY CIT ted a. 22, 1925.

n L. LINDQUIST, 01? HA Tes- PATENT OFFICE.

ars'DALE, NEW YORK, ASSIGNORTO o'rIs ELEVATOR Y, NEW JERSEY, neonrona'rrou or NEW J ns v.

SAFETY MECHANISM. FOR ELE'v'AroRs.

Application filed January 10, 1924. Serial No. 685,345.

4 To all whom it may concern:

Be it known that I, subject of the King 111 Hartsdale, 5 and State of Davin L. LINDQUIST, of Sweden, residing New York, have invented a new and useful Improvement in Safety I Mechanism for Elevators, of which the following is a specification.-

My invention relates to safety mechanisms for elevators,

and more particularly to means for applying safety devices, such for exa carried mple as those in which gripping jaws by the car are adapted to automatically grip the stationary guide rails or other stationary means and thereby stop the car, when the speed becomes" excessive or the hoisting cables part. be desirable to have In certain cases it ma an additional safety device carriedjby the counterweight and adapted to be applied to stop the counter weight 'One when the hoisting cables part.

object of my means for automatically applying the safety car brake or the like has exceeded a predetermined speed and an auxilia ry means for automatically applying the safety in the event of the parting of the main hoisting cables.

Another object is to provide a connection between the safety device on the car and the actuating mechanism, whiclrwill prevent the accidentalapplication \of the safety during the normal operation of the elevator in starting and stopping. Other objects will appearfrom the specificationand Ina tion I*emlp loy a governor driven ernor cab claims. preferred embodiment of my'inve'm by a gove extending throughout the hatch and resiliently connected atone point to the elevator car-b Whenever the y means of a releasing carrier. speed ofthe car exceeds a pree determined amount, .the governor trips its jaws, which thereupon grip the governor cable.. The governor cable is then detached from the car by' disengagement of the releasing also e structu employ auxiliary the governor cable to apply the hoisting cables carrier and th means for gripping part.

.,on- Appliance for elevator safety in the county of Westchester.

mg clamp on the invention 1s to provide j to stop the car when it in the e safety applied; I

the safety whefi present invention involves. certainral' features disclosed in my 'patent devices, Number 1,134,753, dated April 6, 1915.

In the accompanying. drawings whichillustrate various invention,

Figure, 1 1s a diagrammatlc-view of an structures embodying my elevator system to which my invention is applied.

Figure 2 is a diagrammatic view of a safety mechanism adapted to be attached to the bottom of the car.

Figure 3 is a sectional elevation of a hitch tuating cable and the Figure 4 is'a in Figure 3.

governor rope. side view of the hitch shown Figure 5 is a part sectional plan view of.

or connecting device between the safety ac'65- Figure 10 is a diagrammatic, view of a modification in which a safety brake is used on the counterweight to arrest'its movement eve'nt of -parting of the hoisting cables, in addition'to the safety brake on the car. 1

Referrin to Figure 1' the car 0 is lifted and lowers by means ofone'or more hoisting cables 2 attached at one end to the car and extending over the 2' is connected to a counterbalance weight W which, together with a terweightW, is usually of the car plus 40% 01-50% of a full load on the car. 4 counterbalances the shifting weight of the hoistin cables.

In F1gure 2 is shown a safety device com 'pr ising"a safety drum -5.- having a screw threaded connection with a pair of" opposupplemental cram-- equal to the weight traction sheave 3 which is driven from any suitable form of motor.- The opposite end of hoisting cable A compensating cable or chain;

sitely threaded rods 6. These rods are carmed 7 supports 7 secured'to or forming part 0 safety plank 8 (Fig. 1) attached'to the bo t m of thecar; The outer ends of hitch H is the rods 6 are connected through toggle levers 9 to the clamping jaws 10 which normally move freely! over stationary guide rails 11. The drum 5 is adapted to be rotated by means of a cable 12 wound thereon and: at its outer end connected through a hitch H to a governor rope 14 (Fig. 1).

The speed governorsG is o erated by a governor cable 14 which exten s around the governor sheave 15 and a Weighted sheave When the speed of the car becomes excessive, the governor operates a pair of jaws 17 to grip the governor rope 14 so that the car and governor rope causes the. safety I 10 to the formed on the hitch by adjusting nuts 29.

. myinvention is of special value ofthe car,

against withdrawal by nuts Springs 22 bracket 25, the latter ency .55.

-? ing and stopping of the car,

uide rails. The hitell comprises an outer member 30 in the form of a tube provided with internal screw threads .to receive screw-threaded plugs 31 and an inner member 19 adapted to move longitudinally within the outer member 30.

Rods 20 connected to the ends of the governor rope extend freely through the plugs 31 and the ends of member 19 and are held 21. Coil surround the rods 20 and are interposed between the plugs 31 and the ends of member 19. The plugs 31 permit the adjustment of the tension of springs 22. Locking nuts 32 hold the plugs 31 int-he adjust- I ed position. This construction permits a limited movement of the member 19 relative to the member 30 in either direction for a purpose that will be explained later., The

.rope 12 is connected by a'clevis 18 to the member 30. a

The hitch H is connected to the [car through the medium of a releasing carrier K (Figure 5).- This carrier comprises a pair of arms 23 connected by a pivot 24 toa being'rigidly attached to the car. The arms 23 are recessed to receive bosses or spherical projections 26 member 30. A 'coil spring 27 mounted on a rod 28 extended through the arms 23, hitch H witha yieldingrpressure-regulated. e purpose of the resilient connection-between the car and the governor cable 14 is to overcome "of the hitch H to become disconnected from the carrier K during the normal startowingto the in- This feature of on the modcm high speed, high rise elevators. The mass of the governor ro ein such elevators is considerable and reslsts the sudden changes in peed due to the quick starting and'sto ping so that it is necessary, wit :the usual .formiof releasing carrier to clamp the governor rope ertia. of thegovernor cable.

the speed of the car disconnected from the releasing carrier K and the relative movement of the.

H as shown in Figures 3 and 4 "ring 35 sleeve extends through the serves to clamp the the tendto s'tretchin or hitch so tightly as to prevent or at least render uncertain the release of the hitch when the governor operates. In the present construction the pull of the car on the governor cable is transmitted through the'springs 22 so that any sudden change in will compress one of the springs, allowing the governor cable to gradually but quickl take the speed of the car without any un ue strain on the cable and without danger of jerking the hitch loose from the releasing carrier K. This feature of my invention is especially valuable with safety apparatus like. that erein disclosed in which the governor clamp 17 is adapted to permit the governor cable to slip after the gripping jaws on the car have been operated with sufiicient power to effect the-stopping of 'the car under normal load condi tions. With such a construction the gripping power of the governor clamp is limited and therefore the gripping power of the releasing carrier K must be correspondingly limited, so that the resilient connection in the hitch H becomes important in preventing untimely operation of the safety'device.

In Figures 6 and 7 is illustrated a friction hitch or clamp B applied to the governor cable and adaptedto apply the safety under certain conditions as hereinafter noted. The clamp 13 comprises a cylindrical casing or tube 33. Within this tube is a split bushing 34 comprising two members inner surface correspondingly flared.

36 is threaded into the uptube 33.- A coil sprin 37 under compression between the plug an the causes the'bushing 34 to grip the cable 14 with a predetermined pressure. A sleeve 38 surrounds the cable and bears at its lower end against the bushing 34. The lug 36 and has a" screw-threaded connecting therewith.- Theurpose of this sleeve is to prevent the bush- 1ng 34 from being moved upwardly upon the cable and jamming the latter against movement therethrough. Lock-nuts 39 and 40 serveto hold the plug 36 and sleeve 38 respectively in adjusted position. The clamp B- as shown in Figure 1 may be located in a recess41 formed in the counterweight W" which rests on the main counterweight The hoisting cables 2 and govadjustable plug per end of the W. ernor cable 14, may extend through openings 42 and 43"respectively formed in the counterweight W. The. clamp B is spaced vertically from the counterweight W to permita; limited unobstructedrelative movement between clamp B and the vcounterweight, due of the hoisting cables, without operating t e safety mechanism.

' The operation of my invention may be rement of the spring 17'.

the car causes the hitch H to be pulled free from the releasing carrier K and the rope 12 to be drawn out to rotate the safety drum 5 and apply the gripping jaws to the guide rails. When the aws encounter the guide I device to retard the car with full lead at the the-latter no longer moves in unison withthe car, but drops, thus almost immediately rails, further rotation of the safety drum is prevented and the governor rope is then drawn through the clamp 17 until the car is stopped. I prefer to adjust the governor'so that the clamp 17 grips the governor cable with a pressure that will cause the safety maximum rate allowable consistent with the safety of the passengers.

NVhen the hoisting cables break or become disconnected from the car or counterweight,

.engaging clamp B. A pull is then exerted on governor rope 14 through clamp B to detach hitch H from releasing carrier K and apply the safety. The degree of power with which the safety is applied may be regulated in this case by properly selecting the mass of weight W and by the adjustment of the clamping action of clamp B. It will be noted that the pull exerted between rope 14 and clamp B is limited by the gripping action of the jaws 34, so.that any forces resulting from the inertia of VV' will not I result in an excess pull or possible breakage of the governor rope 14.

It is apparent that the safety may be applied with different degrees of power depending upon whether it is actuated by .well as the use of a supplementary Weight.

governor G or by counterweight W and lamp B.

The function of the friction clamp B, as

. W to operate the governor cable, when the hoisting cables part, is to transfer to the governor cable a predetermined limited portion of the total load of the counterweight, for effecting the application of the safety device. Other constructions forperforming this same function are shown in Figures 8 and 9.

Figure -8 illustrates, a modification 'in which the counterweight W is provided.

with a plate or arm 44 projecting into the path of the clamp B. The operation is similar to that described in connection with igure 1.

to the-counterweight This arm carries a non-rotatable pulley 47 around which the governor cable 14 is wound in'one or more Figure 9 shows a furthermodification in which an arm 45 is connected by a pivot 46' loops. The pulley 47 has the same funcplace without applying the safety, since pulley 47 may rocklabout pivot v46. This takes care of variationsin stretching of thehoisting and governor cables in the normal operation of the elevator. The power with which the safety gripping jaws are applied is governed by the amount of-resistance the governor rope offers to the downward movement of the pulley 47.

In FigurelO a safety-brake 52 similar in construction to that illustrated in Figure 2 is provided on the counterweight W. A friction clamp B on governor rope '14 is connected cable 49 to hitch 50. Cable 51 connects hitch 50 to the safety brake 52. Cables 49 and 51 constitute the actuating cable for the safety brake 52. Hitch 50 'is rcleasably held in a releasing carrier K on the counterweight. This releasing carrier is similar to that illustrated in Figure 5. The car C has a safety brake with connections to the governor cable as described in .connection with Figure 1. In the normal operation of the elevator, any difference in stretching. of the hoisting. and governor cable is taken care of without danger of applying safety brake 52 by-leaving the required amount of slack in cable 49. If the hoisting cables 2 part, both the car C and counterweight W drop. This results in de- Consequently the releasing carrier K onthecounterweight is so adjusted as to exert a pull on the cable 14 that will apply the safety on thecar to give the desired retardation. WVhen the car brake. safety has been applied,

the hitch 50 is detached fromthe releasing carrier K on the counterweight. The safety brake 52 on the counterweight is then applied by cable 51. the car C serving as an anchor against which the pull is exerted. The pull on cable 51 is limited by the clamping action of clamp B on governor rope 14. Clamp B is so adjusted that it will slip at a pull somewhat in excess of that required to release hitch 50 from-releasing carrier K on the counterweight. Therefore I v v as'the application of the counterweight safety nears completionythe car brake safety -is more strongly applied until, when. both the car and counterweight have come to' rest, the

safeties on both are each applied with a pull corresponding to the setting of the clamp B, which, as in the previous embodiments, is a predetermined limited portion of the load nected with the governor cable, and a releasing carrier connecting the car with said member.

2. Safety mechanism for elevators comprisin'g in combination with the elevator car, a car brake, a governor cable, a member resiliently connected with said governor cable and having an actuating connection with said car brake, and a releasing, carrier'moving with said car and releasably connected with said member.

3. Safety mechanism for elevators comprising in combination the elevator car, its hoisting cable, a car brake, a speed governor, a governor vcable operated by the car and driving said governor, said governor cable having suitable operating connection with said car brake, means dependent on car speed for operating upon said governor cable to apply the car brake, and'means for operating upon said governor cable to apply the car brake upon breaking of said hoisting cable regardless of the movement of the car.

4. Elevator safety mechanism comprising in combination an elevator car, a counter weight, a car brake, brake operating means, a hoisting cable conn'eeting'the car and the counterweight, and means operative upon the breaking of said hoisting cable to apply to said brake operating means apredetermined limited portion of the total load of said counterweight to effect the application of said car brake.

.5! Elevator safety mechanism comprising -in combination an elevator car, a car brake, p

' in combination the elevator car, its ho1st1ng a brake operating cable, a hoisting cable, acounterweight, and means operative upon the breaking of said hoisting cable to transfer to said brake operating cable a predetermined limited portion of the total loadof said counterweight to effect the application of said car brake;

. 6. Elevator safety mechanism comprising in combination an elevator car, a hoisting cable, a counterweight, a, car brake, a brake operating cable normally moving with said hoisting cable and a friction hitch on said relative movement between itself and said counterweight, but to be acted upon by at least a portion of said counterweight upon the breaking of said hoisting cable, to effect the application of said car brake.

8. Elevator safetymechanism comprising in combination an elevator car, a counterweight, a car brake, brake operating means,

a hoisting cable connecting the car and the counterweight, means operative upon the breaking of said hoisting cable to apply to said brake operating means a predetermined limited portion of the total load of said counterweight to effect the application of said car brake, and means for arresting the fall of the counterweight.

9. Elevator safety mechanism comprising in combination an elevator car, a car brake, car brake operating means, a hoisting cable, a coimterweight, a counterweight brake, means operative upon the parting of said hoisting cable to apply said car brake with a predetermined strength of application, and means dependent upon such application of the car brake to thereafter apply the counterweight brake.

10. Elevator safety mechanism 1 comprising .in combination an elevator car, a car brake,- car brake operating means, a hoisting cable, a counterweight, a counterweightbrake, means operative upon the parting of said hoisting cable to. apply said car brake with a predetermined strength of applica,- tion, means dependent upon such ap lication of the car brake to thereafter appiythe counterweight brake, and means operative upon such application of the counterweight brake to more strongly apply the car brake. 11. Elevator safety mechanism comprising cable, a car brake, a counterweight, a counterweight brake, a brake operating cable, a. I

releasing carrier for operatively'connecting said car brake with said brake operating cable at a given pull, and a releasing carrier for ,operatively connecting said counterweight -brake withsaid brake operating cable, at a greater'p'ull.

a In testimony whereof, I have signed my name to this s ecification.

ilAVID L. 'LINDQUIST.

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